Does a sticky buy now button lift mobile product page sales?

Our mobile product page kept the buy button near the top, so shoppers who read on had to scroll back up to buy. We tested a sticky buy now button, with and without a quantity selector. Over 11 days, conversion fell 8.9% with the quantity version.

Lost Mobile 11 days Called at 90%

SURFACE

Product page

DEVICE

Mobile

VERTICAL

Ecommerce (B2C)

PRIMARY METRIC

Conversion rate

VARIATIONS

2

The hypothesis

By keeping a buy now button on screen as shoppers scroll the mobile product page, we will make buying easier, resulting in a higher conversion rate.

The mobile product page carries a lot of product information below the buy button. Shoppers who read down the page had to scroll back up to buy. A sticky button keeps the next step in reach at every point on the page.

The button sent shoppers straight to checkout. We also tested a version with a quantity selector in the sticky bar, so shoppers could choose how many to buy without scrolling back up.

What we changed

A sticky buy now button, alone or with a quantity selector

Var A added a buy now button that stayed fixed at the bottom of the screen as shoppers scrolled. Var B used the same sticky button and added a quantity selector to the sticky bar. In both versions, the button took shoppers straight to checkout.

VAR A: STICKY CTA

Buy now button fixed to the bottom of the screen
Button goes straight to checkout

VAR B: STICKY CTA + QUANTITY

Buy now button fixed to the bottom of the screen
Quantity selector added to the sticky bar
Button goes straight to checkout

The result

Conversion fell 8.9% with the sticky button and quantity selector

CONVERSION RATE

-8.9%

REVENUE PER VISITOR

-5.8%

VAR A CONVERSION

-5.5%

Over 11 days, the sticky button with a quantity selector (Var B) converted 8.9% worse than the original, and revenue per visitor was 5.8% lower. The sticky button alone (Var A) converted 5.5% worse, with revenue per visitor down 4.4%. Neither version showed any positive movement, so we paused the test after 11 days.

What we took from it

Users preferred the page without a sticky buy now button

A buy now button skips the cart and goes straight to checkout. On this page, that may have asked mobile shoppers to commit before they had finished reading or added more items. Our next step was to retest the sticky button as add to cart, which lets shoppers keep browsing.